Liquid chromatography method for quantification of surface connected mesoporosity in ultrastable Y zeolites

Liquid phase breakthrough experiments were performed in order to characterize the accessible mesoporosity of a dealuminated Y zeolite. The methodology presented herein shows that the use of a bulky molecular probe such as 1,3,5-triisopropylcyclohexane allows discrimination between the occluded mesoporosity accessible via the micropores only, and mesopores connected to the external surface of the zeolite crystals. The results, compared to nitrogen physisorption and mercury intrusion data, show that in commercial ultrastable Y CBV780 zeolite mesoporosity is mainly connected to the surface of the zeolite crystals.